Indicating by-pass assembly



March 5, 1968 w. J. KUDLATY 3, ,7

INDICATING BYPASS ASSEMBLY Filed Oct. 1, 1965 2 Sheets-Sheet 1 |II i [ll 77708. r .3 g4? wad 475V, aw Z/wflr March 5, 1968 w. ,1. KUDLATY 3,371,787

INDICATING BY-PASS ASSEMBLY Filed Oct. 1, 1965 2 Sheets-Sheet 2 United States Patent Ofifice 3,371,787 Patented Mar. 5, 1968 ABSTRACT OF THE DISCLOSURE A filter comprising a housing having an open end; a filter in the housing; a core in sealing engagement with said open end and a separate closure plate removably secured to the core and the open end. A by-pass valve is operatively connected with the filter in the housing; an indicator means is associated with the core outside the housing and means operatively connecting the valve and the indicator means.

This invention relates to a filter housing and has particular relation to an indicating bypass valve assembly and a valve assembly and cover combination for a filter housing.

An object of this invention is an indicating by-pass assembly adaptable to filter housings and systems of different hydraulic pressures.

Another object is a bypass valve assembly adaptable to a system of different pressure by the substitution of a single part.

Another object is a by-pass valve assembly that is economical to manufacture.

Another object is the provision of a valve assembly and end-cap combination of maximum economy and flexibility of choice.

Other objects may be found in the following specification, claims and drawings in which:

FIGURE 1 is a partial longitudinal cross-sectional view of a filter housing utilizing the invention;

FIGURE 2 is a plan view of a closure plate shown in I FIGURE 1;

FIGURE 3 is a cross-sectional view taken substantially along line 3-3 of FIGURE 2;

FIGURE 4 is a top plan view of a different closure plate; and

FIGURE 5 is a cross-sectional view taken substantially along line 5 S of FIGURE 4.

The invention is shown in the drawing embodied in a filter assembly which includes a tubular member 11, a filter 13 mounted in said tubular member and an end fitting 15 closing one end of the tubular member. The end fitting 15 may be secured to the tubular member 11 by welds 17 and has an inlet 19 which connects to a source of unfiltered fluid such as a conduit (not shown). Also formed as part of the end fitting is an opening 21 which is bounded by a fiat surface 23.

A closure assembly 25 is adapted to close the opening 21. The closure assembly includes a flat plate 27 which is adapted to fit over and engage the flat surface 23 of the end fitting 15. A centrally located aperture 29 extends through the flat plate 27. A closure core 31, somewhat in the shape of a truncated cone, is sized to fit in the opening 21 of the end fitting 15 in contact therewith. A peripheral groove 33 is cut in the core to receive an O-ring 35 to form a liquid-tight seal between the core, plate and fitting. An annular flat surface 37 is formed on the base of the core and a cylindrical sleeve 39 is formed to project outwardly from this flat surface. The sleeve 39 is adapted to fit through the aperture 29 of the plate 27 when the flat surface 37 of the core is in contact with the plate.

Located outwardly of the core on. the side thereof opposite to the fiat side 37 is another sleeve 41 connected to the core by a number of spaced legs 43 and extending co-axially in the opposite direction from sleeve 39. The sleeve 41 fits into an axial central passage 45 in the filter 13. Positioned in this sleeve is a valve 47 which is normally closed to prevent flow through the passage 45 of the filter element but will open when the filter element clogs to allow the fluid to bypass the filter through passage 41a. A threaded rod 51 attached to the valve 47 extends through a passage 53 in the core and into the sleeve 39 to connect to a device 55 for indicating the position of the valve 47. Springs 57 and 59 in the sleeve 39 are biased to urge the rod 51 to the closed position of the valve 47. A cover 61, preferably of a transparent material, may be mounted on the plate 27 to cover the valve position indicator 55.

The closure plate 27 is fastened to the closure core 31 by threaded fasteners 65 which extend through openings 67 in the plate and fasten into threaded holes 69 in the core. The openings 67 are counter sunk at 71 to permit the heads 73 of the fasteners to be located below or flush with the outer surface of plate 27. The closure assembly is secured to the fitting 15 by means of threaded fasteners 77 which extend through openings 79 in the plate 27 and into threaded holes (not shown) in the end fitting.

The closure plate 91 shown in FIGURE 4 is similar to closure plate 27 of FIGURE 2, but is thicker. This plate includes a central aperture 93 of the same diameter as the aperture 29 of plate 27, openings 95 to receive the threaded fasteners 65, which openings are counter sunk at 97, and openings 99 to receive fasteners to attach the plate to an end fitting 15. The radial spacing of the openings 95 in the plate 91 are the same as the radial spacing of the openings 67 in the plate 27 to permit interchangeability of these plates with a core 31.

The use, operation and function of the invention are as follows:

The indicating by-pass valve-closure assembly of the invention is adapted to be installed in a hydraulic filter housing where it also functions as a closure for a fitting, such as that indicated at 15, which forms one end of the filter housing. The assembly includes a by-pass valve 47 for the filter 13 and an indicating means 55 to show the exact position of the by-pass valve relative to the by-pass opening 41a in the filter element 13 which is located in the housing 11.

Prior to this invention, indicating closures were made in different thicknesses to correspond to the operating pressure of each particular filter system. Special machining was required in the past to provide a flange on the core to overlie and rest on the end fitting of the filter housing. The disadvantages of the previous constructions have been overcome by this invention in which the assembly is divided into a core 31 which is always the same size and thickness and a separate closure plate that can be constructed in different thicknesses in accordance with the pressure in the system.

The core 31 contains the by-pass valve 47 and its indicator 55, and can be fitted into any filter housing end fitting regardless of the operating pressure of the filter system. The core 31, sleeves 39 and 41 and legs 43 can be die-cast in one piece. The use of a separate closure plate also reduces the amount of the machining required on the core 31 since the closure plate 27 and not the core overlies the end fitting 15 and, therefore, a flange is not required on the core. Interchangeability of the varions-thickness closure plates with a single closure core is obtained by locating the openings for the fasteners at the same radial positions in all plates regardless of thickness of the plate and by also forming the central aperture in the plate of the same diameter in each case. The central aperture is adapted to receive a sleeve 39* formed as part of the closure core and of suflicient length to extend through the central aperture of plates of varying thickness. Thus, the structure of the invention permits the use of a single indicator core 31 with a variety of closure plates depending on the pressure utilized in the particular system.

I claim:

1. A filter comprising a housing having an opening at one end thereof with said opening surrounded by a fiat shoulder, a closure including:

a core formed and adapted to be inserted in said opening in contact with said housing and having a flat annular surface adapted to face outwardly of said housing,

a first cylindrical sleeve formed as part of said core and extending outwardly from said annular surface,

a second cylindrical sleeve extending outwardly from the core On the side thereof opposite to said first annular surface with said second sleeve being coaxial with said first sleeve,

said second sleeve being formed and adapted to engage a filter element positioned in said housing with said second sleeve containing a by-pass valve operatively connected with said filter element,

position indicating means located in said first cylindrical sleeve,

means connecting said by-pass valve with said position indicating means,

a flat plate having a central opening extending therethrough and adapted to receive said first cylindrical sleeve when said plate is positioned in contact with said flat annular surface of said core,

means to removably secure said plate to said flat annular core surface with said plate extending beyond said core,

said plate being adaptable to rest on said shoulder of said housing to support said core in said housing, and

means to removably attach said plate to said housing.

2. The structure of claim 1 wherein a sealing engagement is provided by a seal engaging said core and housing and also engaging said plate.

References Cited UNITED STATES PATENTS 2,017,350 10/1935 Morgan 210452 X 2,620,071 12/1952 Zenick 210450 X 3,313,416 4/1967 Rosanen 210130 X FOREIGN PATENTS 826,690 1/1960 Great Britain.

SAMIH N. ZAHARNA, Primary Examiner. 

